Pollutant Concentrations

Air quality readings will be available hourly from 7am to 11pm. Air quality readings from 12am to 6am will be made available at 7am on the same day.

Readings on 13 Dec 2014

View reading for:

Region

24-hr Sulphur dioxide(µg/m3)

24-hr PM10(µg/m3)

1-hr Nitrogen dioxide(µg/m3)a

8-hr Ozone(µg/m3)

8-hr Carbon monoxide(mg/m3)

24-hr PM2.5(µg/m3)

North

6(4)

23(23)

32(-)

42(18)

0.3(3)

12(50)

South

4(3)

22(22)

7(-)

26(11)

0.4(4)

11(44)

East

5(3)

20(20)

15(-)

47(20)

0.3(3)

12(51)

West

5(3)

27(27)

28(-)

20(8)

0.5(5)

15(54)

Central

9(6)

20(20)

58(-)

35(15)

0.3(3)

10(44)

1-hr PM2.5 (µg/m3)b Readings on 12 Dec 2014

View reading for:

Time

1am

2am

3am

4am

5am

6am

7am

8am

9am

10am

11am

12pm

North

15

17

9

11

14

5

6

5

11

13

17

16

South

8

10

8

11

8

8

8

8

12

22

16

11

East

11

12

19

20

15

17

17

9

10

15

8

15

West

20

23

13

21

16

8

18

15

8

18

17

13

Central

8

14

12

10

10

11

4

10

8

12

13

11

Time

1pm

2pm

3pm

4pm

5pm

6pm

7pm

8pm

9pm

10pm

11pm

12am

North

19

16

12

11

14

12

8

14

11

7

9

13

South

18

13

15

16

13

8

7

9

6

7

5

4

East

10

11

8

13

6

13

8

13

7

10

12

11

West

10

13

13

14

11

11

20

26

13

8

17

6

Central

15

15

9

14

8

11

11

11

9

11

4

5

Note:a Sub-index for nitrogen dioxide is reported only when the 1-hr concentration equals or exceeds 1130 µg/m3.

b There is no sub-index for 1-hr PM2.5.

3-hr PSI Readings from 1am to 12am on
12 Dec 2014

Time

1am

2am

3am

4am

5am

6am

7am

8am

9am

10am

11am

12pm

3-hr PSI

52

53

52

53

52

51

46

43

42

50

53

54

Time

1pm

2pm

3pm

4pm

5pm

6pm

7pm

8pm

9pm

10pm

11pm

12am

3-hr PSI

53

53

52

52

50

49

45

51

48

45

38

36

Hourly updates of 3-hr PSI readings are provided from 7am to 11pm. The 3-hr PSI readings from 12am to 6am will be made available at 7am on the same day. The 3-hr PSI readings are calculated based on PM2.5 concentrations only.